Project Summary/Abstract Low back pain (LBP) is a leading cause of disability and expense in the U.S. Maladaptive beliefs about pain and physical activity are central risk factors for development and maintenance of LBP. Individuals with elevated maladaptive pain beliefs become trapped in a cycle of continued pain and disability through avoidance of common physical activities which they associate with harm and (re)injury. The proposed project will capitalize on recent mixed-reality gaming technologies in combination with an innovative robotic walking treadmill system to develop an individualized, high-quality, intervention designed to challenge maladaptive beliefs and promote physical function/reduce disability. People with LBP can benefit from daily, vigorous walking regimens to prevent secondary complications and improve psychological and social well-being. This project integrates a VR-gaming platform with an existing robotic treadmill-based walking apparatus. The robotic treadmill system takes advantage of the user?s ability to drive the treadmill belt speed and steer the rotational and vertical direction of their body, and the ability of the apparatus to deliver both assistive and resistive forces horizontally against the person?s body. This Phase I SBIR will comprise development of the gaming intervention based on existing prototypes, as well as user feasibility and effect size estimation. A subsequent SBIR Phase II project will streamline the current system in order to reduce costs and promote access to and dissemination of intervention to a wide range of users within public fitness centers and other health-related environments. Our application proposes the following aims: Aim 1: To develop and implement a VR-gaming platform that provides progressive and accessible walking challenges for individuals with chronic LBP and high pain-related fear by utilizing visual, interactive, and motivational elements afforded by a mixed-reality paradigm. In total, this system will generate a gaming environment where an individual with chronic LBP can experience accessible challenges and control their walking experience in a variety of motivational and inspirational settings. Aim 2: To determine the feasibility of the VR-gaming walking platform for individuals among chronic LBP and high pain-related fear, and to calculate effect-size estimates for maladaptive pain beliefs, self-reported pain, disability, and walking performance in the VR-gaming environment. Participants will be asked to engage in structured performance designed to challenge an individual to walk further and faster and against greater physical challenge. The proposed project is significant, innovative, and timely because it will (a) represent the first application of VR-gaming to promote walking behavior among individuals at risk for continued back pain and disability, (b) provide a platform for future treadmill and other walking products adapted to home, community, and clinical settings, and (c) has the potential for important public health impact by incorporating a therapeutic modality into low-cost and widely accessible technology, thereby allowing large-scale treatment provision and testing.